370z humming and cabin vibration at 70
 

Hru guys I have a 09 370z stock 6 sp manual that I just bought. Had driveshaft replaced due to grease sling on ujoints. I figured that would've fixed my vibe. At 70mph and I let off gas and slowly press gas it has a fluttering vibration in back hatch area. At 75 to 80 mph I hear a low hum from the driveline.....any suggestions I can feel vibe in seat and gas pedal. Thanks

Is this your first manual transmission?

Nope ive had 2 wrx sti 2011 5.0 mustang and two other z cars